1. Field of the Invention
The present invention relates to a device for use in a continuous slab casting process and more particularly to a portable mold adjusting device for relatively precisely adjusting the mold cavity size of slab casting molds both during casting and between casts.
2. Description of the Prior Art
The continuous casting process involves a continuous flow of molten steel from a ladle or tundish into a generally box-shaped casting mold to form a slab. Since the slabs are generally cast with a uniform thickness but various widths, for example, 24 to 50 inches, the slab mold is formed with a pair of stationary mold walls and a pair of adjustable mold walls. More specifically, the stationary mold walls are generally rigidly mounted and spaced apart a predetermined distance to form slabs having a uniform thickness between 4 and 12 inches. The adjustable mold walls are disposed between the rigidly mounted mold walls intermediate the ends to allow the Width of the slabs to be varied, for example, between 24 and 50 inches.
The mold walls are typically formed with heavy fabricated steel with inner facings usually of copper. Cooling channels are generally disposed between the inner facings and the heavy fabricated steel walls. Cooling water is circulated through the cooling channels to remove heat from the molten steel to initiate solidification of the molten steel within the mold.
Slab casting molds have heretofore been provided with integral means for adjusting the slab widths. More specifically, various devices including hydraulic cylinders have been mechanically linked to the adjustable mold walls to move the adjustable mold walls either inwardly or outwardly to vary the width of the slab. Due to the relative inaccuracy of such known adjustment means, the slab widths are generally adjusted between casts and have not generally been known to be adjusted during the casting process only between casts. This, in turn, increases the production time to produce slabs with various widths.
Such slab casting molds with integral adjustment means generally increase the cost of the molds and have been known to result in increased cost to the end user. More specifically, many steel mills have been known to operate a plurality of continuous casting lines. Thus, in such situations, since each slab casting mold is provided with integral adjustment means, the overall cost is relatively high.
Another problem with such slab casting molds is that the integral adjustment means have been known to require a significant amount of maintenance. Such maintenance time results in downtime of the caster resulting in lost profits.